Gemini 3.1 Flash Lite vs GPT-5.1-Codex-Max
Gemini 3.1 Flash Lite costs 6.7x less per output token than GPT-5.1-Codex-Max ($1.50 vs $10.00 per million). Updated October 21, 2026; no benchmark has tested both models yet.
- Coding
- No data
- Overall
- No data
- Output $/M
- $1.50
- Coding
- No data
- Overall
- No data
- Output $/M
- $10.00
Gemini 3.1 Flash Lite or GPT-5.1-Codex-Max: which to pick
Neither model has a coding score yet, so the two cannot be ranked on coding.
Pick Gemini 3.1 Flash Lite for output tokens 6.7x cheaper ($1.50 vs $10.00 per million) and a larger context window (1.05M against 400K tokens).
No benchmark has tested both yet. Gemini 3.1 Flash Lite has results on SciCode, Terminal-Bench Hard (Artificial Analysis run) and WeirdML; GPT-5.1-Codex-Max on LiveCodeBench (Vals AI), Vibe Code Bench (Vals AI) and Terminal-Bench. Compare them on price and context instead.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
No call
Neither has a coding score yet.
One side not measured
Long documents
Listed context window
Gemini 3.1 Flash Lite
Gemini 3.1 Flash Lite takes 1.05M tokens against 400K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3.1 Flash Lite
Gemini 3.1 Flash Lite $0.0010, GPT-5.1-Codex-Max $0.0063 per turn.
List prices
At a glance
- Coding index
- Gemini 3.1 Flash Lite not benchmarked, GPT-5.1-Codex-Max not benchmarked.
- Widest category
- None yet: no category has been tested on both models.
- Widest single gap
- None yet: no benchmark has tested both models.
- Output price
- Gemini 3.1 Flash Lite $1.50 against GPT-5.1-Codex-Max $10.00 per million output tokens, 6.7x apart.
- Context window
- Gemini 3.1 Flash Lite takes 1.05M tokens, GPT-5.1-Codex-Max 400K.
Benchmark by benchmark
Every board either model has a result on, a category to a fold; bars are each result on a 0 to 100 scale. Only one model is measured on each, so no row names a leader.
CodingDirectional onlySix of these boards feed the Vibe Coding Index7 boards measured
| Benchmark | Gemini 3.1 Flash Lite | GPT-5.1-Codex-Max | Leader |
|---|---|---|---|
| LiveCodeBench (Vals AI) | Not measured | 83.6% | Only GPT-5.1-Codex-Max measured |
| Vibe Code Bench (Vals AI) | Not measured | 22.2% | Only GPT-5.1-Codex-Max measured |
| SciCode | 43.4% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Terminal-Bench Hard (Artificial Analysis run) | 24.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Terminal-Bench | Not measured | 60.4% | Only GPT-5.1-Codex-Max measured |
| WeirdML | 52.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| ALE-Bench | Not measured | 1228.3 | Only GPT-5.1-Codex-Max measured |
| Neither model has a result on the other 32 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index1 board measured
| Benchmark | Gemini 3.1 Flash Lite | GPT-5.1-Codex-Max | Leader |
|---|---|---|---|
| Epoch Capabilities Index | 144.3 | Not measured | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 1 board here | |||
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index3 boards measured
| Benchmark | Gemini 3.1 Flash Lite | GPT-5.1-Codex-Max | Leader |
|---|---|---|---|
| τ²-Bench Telecom | 31.3% | Not measured | Only Gemini 3.1 Flash Lite measured |
| METR time horizons | Not measured | 70.8% | Only GPT-5.1-Codex-Max measured |
| DeepResearch Bench | 37.3% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 38 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index4 boards measured
| Benchmark | Gemini 3.1 Flash Lite | GPT-5.1-Codex-Max | Leader |
|---|---|---|---|
| GPQA Diamond (Artificial Analysis run) | 82.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Humanity's Last Exam (Artificial Analysis run) | 17.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| GPQA Diamond (Epoch AI run) | 81.8% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Kagi LLM Benchmark | 67.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 18 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index3 boards measured
| Benchmark | Gemini 3.1 Flash Lite | GPT-5.1-Codex-Max | Leader |
|---|---|---|---|
| OTIS Mock AIME | 80.0% | Not measured | Only Gemini 3.1 Flash Lite measured |
| FrontierMath, tiers 1 to 3 | 27.7% | Not measured | Only Gemini 3.1 Flash Lite measured |
| ProofBench | Not measured | 9.0% | Only GPT-5.1-Codex-Max measured |
| Neither model has a result on the other 10 boards here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index4 boards measured
| Benchmark | Gemini 3.1 Flash Lite | GPT-5.1-Codex-Max | Leader |
|---|---|---|---|
| IFBench | 77.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Long context reasoning (AA-LCR) | 74.3% | Not measured | Only Gemini 3.1 Flash Lite measured |
| DTBench | 76.8% | Not measured | Only Gemini 3.1 Flash Lite measured |
| LMCA | 35.0% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 42 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Gemini 3.1 Flash Lite costs less
Repository review
50K input + 3K output tokens
Gemini 3.1 Flash Lite costs less
Agent loop
200K input + 10K output tokens
Gemini 3.1 Flash Lite costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | Google Gemini 3.1 Flash Lite | OpenAI GPT-5.1-Codex-Max |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | No public weights listed |
| Released | May 7, 2026 | December 4, 2025 |
| Context window | 1.05M | 400K |
| Input $/Mtok | $0.25 | $1.25 |
| Output $/Mtok | $1.50 | $10.00 |
| Coding index | Not benchmarked | Not benchmarked |
| Independent measurements behind it | 0 | 1 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.1 Flash Lite better than GPT-5.1-Codex-Max for coding?
Neither model has a coding score yet, so the two cannot be ranked on coding. Pick Gemini 3.1 Flash Lite for output tokens 6.7x cheaper ($1.50 vs $10.00 per million) and a larger context window (1.05M against 400K tokens).
Which is cheaper, Gemini 3.1 Flash Lite or GPT-5.1-Codex-Max?
Gemini 3.1 Flash Lite costs $0.25 per million input tokens and $1.50 per million output tokens; GPT-5.1-Codex-Max costs $1.25 and $10.00. Cost per solved task is known for neither of them.
Which has the bigger context window, Gemini 3.1 Flash Lite or GPT-5.1-Codex-Max?
Gemini 3.1 Flash Lite, with 1.05M tokens against 400K.
Has any benchmark tested both Gemini 3.1 Flash Lite and GPT-5.1-Codex-Max?
No benchmark has tested both yet. Gemini 3.1 Flash Lite has results on SciCode, Terminal-Bench Hard (Artificial Analysis run) and WeirdML; GPT-5.1-Codex-Max on LiveCodeBench (Vals AI), Vibe Code Bench (Vals AI) and Terminal-Bench. Compare them on price and context instead. Data as of October 21, 2026.